Lupus is a group of conditions with similar underlying mechanisms involving autoimmunity. In these conditions antibodies created by the body to attack antigens (e.g., viruses, bacteria) became unable to differentiate between antigens and healthy tissue. Thus, the antibodies that should protect the body begin to attack the body's own healthy tissues. Triggers for lupus include viruses, bacteria, allergens (both IgE and hypersensitivity), hormones (e.g., estrogens), environmental stimulants (e.g., ultraviolet light, sunlight, stress, smoking, trauma, scratching, burn, coldness), and certain medications.
Lupus is generally a chronic disease in which the signs and symptoms tend to come and go. Common signs or symptoms of lupus include, for example, joint pain and stiffness; muscle aches, pains, or weakness, fever with no known cause; feeling very tired; butterfly-shaped rash across the nose and cheeks; other skin rashes; unusual weight loss or weight gain; anemia; trouble thinking, memory problems, and confusion; kidney problems with no known cause; chest pain when taking a deep breath; sun or light sensitivity; hair loss; and purple or pale fingers or toes from cold or stress. Less common symptoms include blood clots, seizures, strokes, sores in the mouth or nose, severe headache, dizzy spells, “seeing things” or not being able to judge reality, feeling sad, and dry or irritated eyes. Lupus also increases the risk of developing various other diseases and/or causes other diseases to occur earlier in life. Such diseases include heart disease, osteoporosis, and kidney disease. See, e.g., Lupus Fact Sheet by the U.S. Department of Health and Human Services, Office on Women's Health (womenshealth.gov/publications/our-publications/fact-sheet/lupus.cfm; accessed Jun. 18, 2012).
Types of lupus include, for example, systemic lupus erythematosus (SLE), cutaneous lupus erythematosus (CLE) (CLE includes, e.g., acute cutaneous lupus erythematosus (ACLE), subacute cutaneous lupus erythematosus (SCLE), intermittent cutaneous lupus erythematosus, and chronic cutaneous lupus), drug-induced lupus, and neonatal lupus. About 70% of all cases of lupus are SLE. CLE can have symptoms that are limited to the skin or can be seen in those with SLE.
Lupus affects predominately young women. More than 90% of people with lupus are women between the ages of 15 and 45. African-American, Latina, Asian, and Native American women are at greater risk of developing lupus than are white women. Men are at higher risk for developing lupus before puberty and after age 50. For African-American women between the ages of 15 and 64, the prevalence is one per 245 women. This prevalence rate for African-American women makes lupus one of the most common chronic diseases of this population. See, e.g., lupus.org/webmodules/webarticlesnet/templates/newempty.aspx?articleid=413&zoneid=99, accessed Jun. 18, 2012.
Fibrotic conditions include diseases that involve the formation and/or deposition of fibrous tissue that builds up and/or spreads over or replaces normal organ tissue. Fibrotic conditions occur when processes that normally contribute to wound healing go awry, resulting in extra scar tissue that can be harmful. Fibrotic conditions can affect single organs or tissues, or they can be systemic and affect multiple organs or tissues of the body. Examples of systemic fibrotic diseases include atherosclerosis, scleroderma, nephrogenic systemic fibrosis, cystic fibrosis, and chronic graft vs. host disease. Fibrotic conditions can affect almost any part of the body. For example, fibrotic conditions can affect the lungs, heart, skin, kidneys, bone marrow, liver, and eyes.
Fibrotic conditions affect a large portion of the population; atherosclerosis alone will affect about 25% of Americans in their lifetime. Fibrotic conditions have serious consequences for quality of life. Examples of serious consequences of fibrotic conditions include difficulty breathing, kidney failure, and blindness. Furthermore, fibrotic conditions are often fatal. Indeed, tissue fibrosis contributes to 45 percent of all deaths in developed countries.
Inflammatory myopathies are diseases that typically involve inflammation of the muscles and associated symptoms, such as muscle weakness. The muscle weakness can be progressive and can lead to difficulty moving, including difficulty walking, breathing, swallowing, and talking. Inflammatory myopathies can be caused by allergic reactions, other diseases, exposure to a drug or toxin, or exposure to an infectious agent, or they can be idiopathic (no known cause). Inflammatory myopathies include dermatomyositis, polymyositis, inclusion body myositis and immune-mediated necrotizing myopathies. In some cases, dermatomyositis involves predominantly skin symptoms, without muscle symptoms, or without noticeable muscle symptoms. Inflammatory myopathies can affect both adults and children (e.g., juvenile dermatomyositis). Inflammatory myopathies can include symptoms that affect other organs or systems of the body, such as the skin, lungs, heart, eyes, and gastrointestinal system. Although inflammatory myopathies are relatively rare, their prevalence has likely been underestimated (see, e.g., Smoyer Tomic, K. C. (2012) BMC Musculoskeletal Disorders, 13:103) and they can cause serious and even fatal symptoms or complications.
Inflammatory skin conditions, such as skin rashes, including rashes caused by allergens or other diseases, are commonplace. Skin rashes are frequently painful and/or itchy (pruritic) and can be debilitating. Associated symptoms such as hay fever are likewise uncomfortable and can be debilitating. Allergic reactions can also have serious consequences, such as anaphalaxis.
Accordingly, there is a need for effective treatments for lupus, fibrotic conditions, inflammatory myopathies, skin conditions, and associated symptoms.